Field of the Invention
The present invention relates to a clip unit used to ligate a tissue.
Description of Related Art
Ligation devices including clip units have been used to ligate openings formed in tissues or blood vessels. As such a clip unit, for example, an endoscope treatment tool disclosed in Japanese Unexamined Patent Application, First Publication No. 2010-221059 has been known.
The clip unit disclosed in Japanese Unexamined Patent Application, First Publication No. 2010-221059 is configured to include a claw, a pressing tube, and a connection plate. The claw is a portion in which a halfway portion is bent in an a shape and both ends thereof are formed in a claw shape. An arm portion of the claw is configured to be opened slightly by elastic resilience of the arm portion of the claw in a released natural state.
In the connection plate, a hole is provided in a hand-side end portion and a hook portion is formed in a distal-end-side end portion. The hook portion is hooked to a proximal-end-side loop portion of the claw so as to be disposed inside the pressing tube. At this time, the α portion of the claw is not drawn deeply into the pressing tube and the arm portion of the claw can be opened slightly.
The clip unit having the above-described configuration which is disclosed in Japanese Unexamined Patent Application, First Publication No. 2010-221059, is introduced into the body cavity by using an endoscope ligation device. The endoscope ligation device includes an introduction tube, a manipulation wire (linear member), a manipulation portion main body, and a slider. A coil sheath is inserted so as to be advanceable and retractable inside the introduction tube. The manipulation wire is inserted so as to be advanceable and retractable inside the coil sheath. The manipulation portion main body is attached to the proximal end of the coil sheath. The slider is configured to be attached to the proximal end of the manipulation wire via a pipe and to be slidable with the manipulation portion main body. The above-described clip unit is attached to the distal end of the manipulation wire.
A halfway portion of the manipulation wire is turned back through the hole of the connection plate. Portions on both sides of the manipulation wire formed as two wires by turning back the halfway portion are inserted parallel to each other so as to be advanceable and retractable inside the coil sheath. The slider is fixed on the both proximal ends of the manipulation wire. The pipe is fitted to the both proximal ends of the manipulation wire.
The clip unit and the endoscope ligation tool having the above-described configuration are used as follows.
The clip unit is accommodated inside the introduction tube. The introduction tube of the endoscope ligation device in this state is inserted into a channel of an endoscope which has been inserted into a body cavity in advance. After the distal end of the introduction tube reaches inside the body cavity, the introduction tube is pulled toward the hand side to make the clip unit to protrude from the distal end of the introduction tube.
By pulling the slider toward the hand side with a light force, the α portion of the claw is drawn inside the pressing tube to open the claw more widely. In this state, the introduction tube is pushed into the endoscope to press the opened claw against a target bleeding site or the like inside a body cavity.
In this state, when the slider is strongly pulled toward the hand side, the proximal end of the arm portion is drawn to the pressing tube so that the claw is closed and the tissue of the bleeding site is grasped. When the slider is pulled more strongly, the hook portion of the connection plate is stretched so that the clip unit is separated from the endoscope ligation device and detained inside the body cavity while the clip unit grasping the tissue.